THE DISTRIBUTION, NUMBERS AND BREEDING ECOLOGY OF TWITE ACANTHIS-FLAVIROSTRIS IN THE SOUTH PENNINES OF ENGLAND

This study used the results of a systematic upland bird survey conduct ed in 1990 and the information held on BTO nest record cards to study the distribution, numbers and breeding ecology of Twite Acanthis flavi rostris in the south Pennines of England. The survey estimated the siz e of the population as between 200 and 400 pairs. The distribution of records obtained during the survey is mapped. In the breeding season, Twite show an association with relatively low-altitude sites at the mo orland edge, especially where the length of reservoir or river shore t ends to be large and the sward height exceeds 5 cm. They apparently av oid areas dominated by Juncus spp. flush vegetation. We compare inform ation available on BTO nest record cards for south Pennines Twite with those from Scotland. Breeding performance for Twite nesting in heathe r-dominated habitats was better than for those nesting on either grass -dominated or other moorland habitat. Twite brood-size in the south Pe nnines has declined in recent years and nest failure rates have appare ntly increased. This may indicate that, through reduced recruitment, a decline in the size of the breeding population is likely. Current upl and management practices may not be ideal for maintaining breeding Twi te in Britain.